Improvement in processes of rendering cast-iron malleable



'J ITED STATES PATENT OFFICE.

LEXANDER H. SIEGFRIED, OF LEWIsBURe, PENNSYLVANIA.

Specification forming part of Letters Patent No. 131,634, datedSeptember 24, 1872 To all whom it may concern:

Be it known that I, ALEXANDER H. SIEG- FRIED, of Lewisburg, Unioncounty, State of Pennsylvania, have invented a new Method of Rendering(last-Iron Malleable, of which the following is a specification:

My invention relates to the preparation of malleable iron from cast-ironby mixing with the molten fluid iron, before running into molds, acertain chemical compound, and then immersing in a bath or pickle theobject cast, said bath containing, in solution, certain chemicals, andthen annealing the casting so treated.

The compound which I mix with the molten iron is composed of thefollowing ingredients inthefollowing proportions, viz. Concentrated lye,one pound; sal-soda, one pound; sulphate of copper, one and one-halfpound; sal-ammoniac, one pound; sulphate of potash, onefourth pound;nitrate of potash, one-fourth pound; common salt, three and one-fourthpounds. I use of this compound from four to five pounds to every hundredpounds of iron to be treated. This compound may be mixed with the ironwhile still in the furnace, or may be mixed with the molten iron afterit is drawn from the furnace .into the ladle and ,before it is pouredinto the molds. hen the former method is adopted the iron is meltedquite thin, and the damper to the furnace is closed and the blast takenoif, and the compound put into the. iron and the mass worked thoroughlyfor a few minutes; then the damper is opened and the blast put on and astrong flame created, so as to expel the gases and other impurities.When the compound is put into the ladle the iron should be stirredfreely,

that a thorough mixture may take place. The metal into which thiscompound has been put having been run into the molds, I take out thecasting while it is at a low cherryred heat and plungeit in a bath orpickle composed of the following ingredients in the followingproportions, viz.: Water, one gallon; v

Claims.

What I claim as new, and desire to secure by Letters Patent, is-

1. The employment, in' making malleable iron, of the processessubstantially as described above.

2. The compound herein described for mixing with molten iron prior toits being run into molds.

3. The bath hereinb'efore described for treating cast-iron.

. 4.. The use, in making malleable iron, of the compound and bath, ashereinbefore substantially described.

In testimony whereof I have signed my name to this specification beforetwosubscribing witnesses.

ALEXANDER H. SIEGFRIED.

Witnesses:

OHAs. A. 'NEALE, ROBT. V. HUGHES.

